I have to wonder if motivations remain the same past a certain point in a species' development. Our expansionism on earth and in our solar system is driven by our need for resources, which is driven by our population growth, which is driven by the basest of biological instincts. If we become largely non-biological and functionally immortal, is the desire to procreate still there? It's really an extension of what you said, but maybe that "turn inward" is not only a question of feasibility, but also maybe intelligent life just becomes satisfied at some point, a kind of cybernetic nirvana.